Why hasnt anyone come up with a teflon ring in-lieu of the rubber crap? I remember replacing one the rubber ones, and the smith lubed it after replacing. Then at zero temps it froze up. Teflon would last forever and never need to be lubed.
I'm not sure teflon would work forever. Teflon has great temperature, chemical and low friction properties, but it has drawbacks (see below). Choosing the right material is a balance of compromises for temperature ranges, chemical resistance and mechanical properties.
PTFE is not a rubber compound, but a white thermoplastic resin which can be formed into various shapes by either machining or molding. It is a premium grade material which is often specified in harsh chemical environments where no rubber material is suitable as it is impervious to virtually all fluids and gases. PTFE exhibits very low moisture absorption and can withstand extreme high and low temperatures. It also provides the lowest coefficient of friction of any seal material. One major drawback to using PTFE is its tendency to deform under a continuous load, a phenomenon commonly known as creep or cold flow. Loading PTFE with fillers such as bronze, graphite, glass, or molybdenum disulfide can counteract this behavior substantially. PTFE also has relatively poor elasticity compared to other sealing materials.
I just ordered an array of o-rings from
TheOringStore.com for $8.44 shipping included. I didn't want to spend the dollars for just a single o-ring from Remington or MidwayUSA. The Remington o-ring part number is F15215 and costs $4.37 + $6 shipping from Remington. MidwayUSA charges $5.99 and according to one reviewer, $8 shipping. However, ordering one on your own leaves you with having to figure out what material and size you need. The material Remington uses is viton, not your typical rubber o-ring found at the plumbing or hardware store. However, there are several different choices of viton o-rings with differing properties. I also looked at teflon, nitrile and polyurethane o-rings. I ruled out teflon but I am getting a few polyurethane and nitrile o-rings as well as some vitons. The prices are cheap enough that shipping is the largest cost factor.
As for size, from some online searching I found a post from another forum stating the 760's o-ring is 0.5" ID and 0.06 thick. I also measured mine to be 0.5" ID and ~1/16" thick. That corresponds to a
number 014 size o-ring which is nominally 0.5" ID, 1/16" or 0.070 +/- .003 thick and 5/8" OD (
O-ring Size Chart).
I think the biggest issues with the o-ring failures are cold temps, grit in the action tube, harsh chemicals from gun cleaners and poor lubes or no lube. The viton is resistant to a lot of harsh chemicals, but not all of them. So I wouldn't shoot gun scrubber, carb cleaner or acetone up inside the action tube where the o-ring is, unless you've disassembled it and removed the o-ring first, and only use a lube that's good for cold temps and friendly to o-rings. It's not that difficult to disassemble and clean a 760/7600. You just need the right tools and the know-how =>
Gunsmithing Disassembly: Remington 7600 (Gunworks) .
